So on my 2001 E 350 Superduty Diesel. I see online and everywhere else that I don't have a Glow Plug Relay. I supposedly have a Glow Plug Controller. Thats the electronic aluminum box with two connectors going into it. I can't find that thing on my Van for nothing. What I do see is two solenoids on the front passenger side right where the Truck solenoids are suppose to be. So I am scratching my head wondering why I would have this setup instead of what I am supposedly suppose to have. Obviously it would be the solenoid in the rear of the front one. The van smokes like a steam train when cold, only will start with a tiny tiny shot of starting fluid and If I do have the traditional mechanical Glow Plug Relay. It does not click when i turn the key forward.
Now for the Ford guys that know everything. My E350 Superduty is actually one of the Incomplete Chassis carrying a 14' cube box on the back with duallies. Maybe thats the reason for the other solenoid instead of the one claiming to be for my van. Anybody know what I am talking about and can clairify this?

 

I cannot clarify if you do or do not have a GPCM (GlowPlug Control Module), or as you called it Glow Plug Controller.

If you do it will look like this and is in the center of your motor just to the left, near your fuel filter.

 

To check the relay (if that's what you have) is real easy. Put a volt meter
on both large dia. posts, 1 will have 12+ volts the other won't, turn on the
key and check if you have voltage at the one that didn't have any before.
If you have voltage now then replace ALL glow plugs instead of trying to
find bad ones. If you don't have voltage, replace gpr

 

Well, now I know I have a standard GPR like most of the trucks. I read somewhere that alot of the electronic ones were on cali emission vehicles. Besides, I changed mine today and it works good now. I went to napa they didn't have any more GPR 109's, so I just bought the properly fitting GPR 110. Every repair is a great learning experience.